Dynamics of the deformation and destruction of a heterogeneous body (granite) under the influence of an electric discharge

The device is constructed, which makes it possible to simultaneously detect, with a time resolution of 10 ns, fractoluminescence as well as electromagnetic emission and surface deformation observed in a solid during its destruction under the effect of a shock wave. Using this device, time dependences of deformation and destruction of the granite plate caused by an electric breakdown with an energy of 0.2 J in air near its surface are investigated. It is found that the breakdown causes the appearance of a shock wave in granite, the velocity of which is $\sim$ 5 km/s. The shock wave stimulates emission of a plasma consisting of atoms and ions, which enter into the graphite composition, from the granite surface. It is assumed that the appearance of the plasma is caused by cumulation of the shock wave energy in micropores contained in graphite.